There are already a large number of material and constructional combinations in the field of motor vehicle wheels.
Welded sheet steel wheels are mainly used in the mass production of cars. Multi-part cast light metal wheels are also known, whereby the individual parts thereof are interconnected by screws. Three-part wheels also exist comprising a solid cast spider and light sheet metal rim bed halves fixed thereto. Sheet steel wheels comprising two or more parts also exist which are not welded and instead are riveted. Cast and forged light metal wheels also exist. In the case of motorcycle wheels, hitherto rims have been used which have been connected with the hub made from sheet steel or cast light alloy by means of steel wire spokes. Of late, light metal wheels have been used, but these are only cast.
In view of the very varied requirements made regarding vehicle wheels, it is also necessary to accept a compromise. The main requirements are a minimum weight because the non-spring-mounted masses which includes the wheels influence the travelling behaviour of the vehicle, and, naturally, an adequate strength. The manufacturing costs are also an important factor. It is difficult to combine together these three factors in an optimum manner. Although sheet steel is relatively inexpensive, and does not prove costly in the manufacture of wheels, it is nevertheless relatively heavy.
In addition, sheet steel must be varnished or painted and is subject to considerable corrosion phenomena. Although light alloy has the same strength and is lighter, it has hitherto only permitted the manufacture of wheels by casting methods.
An exception is formed by a vehicle wheel with a double wheel disc according to German Offenlegungschrift No. 2,443,088. This vehicle wheel comprises identical light metal pressings fixed to a hub member, whereof each forms a half of the rim bed. In this construction, the two light metal pressings, whereof each forms a half of the rim bed, are joined together by a plurality of sleeve nuts, whose sleeves have an internal thread. These assembly nuts at the same time serve to fix the complete wheel to the vehicle axle flange. These sleeve nuts are expensive to manufacture. Further, the use thereof as connecting members between the two light metal pressings, while at the same time serving as means for fixing the wheel to the axle flange, leads to mechanical and loading disadvantages. In addition, such wheel is not tight, especially as the two light metal pressings have ventilation holes. The space between the two light metal pressings is filled by an elastomer material. Such a wheel is very expensive to manufacture and assemble.